This invention relates generally to curtain walls and, more particularly, to a water-tight and heat insulating joint structure between adjacent units of a unit type curtain wall.
The joint structure between adjacent units of a unit type curtain wall is required to be effectively water-tight to prevent water from entering the room even when rain water is forcefully striking the outer surface of the curtain wall such as in a storm.
Japanese Utility Model Publication No. 57-12654 discloses a joint structure between adjacent units of a unit type curtain wall. In this structure, an air space is defined between the outer and inner sides of the curtain wall. The air space has a portion communicating with the external atmosphere, while it is sealed on the side nearer the room and on the side opposite the room except for the communicating portion. With this structure, even if water intrudes into the seal section on the side of the air space opposite the room from the outer surface of the unit type curtain wall, it will not be forced into the air space because the air pressure in the air space is the same as the atmospheric pressure. In the event of water slightly entering the air space, it no longer has sufficient momentum to clear the seal section between the air space and the room.
In the disclosed structure noted, however, the temperature of the air in the air space is the same as the atmospheric air temperature for the air space communicates with the external atmosphere. Since frames of the adjacent curtain wall units at the joint are exposed to this air in the air space, the disclosed structure does not have excellent heat insulation effect.